Which do you like best and why?
In what caliber?
I've not researched the Winchester product, but did test Hornady CD. IMO the FTX bullet isn't anything great, but it is by no means bad. I'm sure it will work well in .40 S&W since it's a hard caliber to screw up. My hunch is that the Winchester bullet is as reliable of an expander and probably bonded, so I'm thinking it is a better choice.
I agree with Flopshank. I have tested both in water jugs in the .38+P caliber. The CD is very uniform and repeatable. But it was just a little smaller than the PDX1. The PDX1 is bonded. It may not do as well with going through clothing as the CD. In .45ACP the PDX1 produces a wicked looking mushroom (like the Ranger SXT/Black Talon). I would probably go with the PDX1. B